Most of the data collected by car companies goes well beyond anything related to operating your vehicle, according to the 2026 Car Brand Privacy Study by All About Cookies. While car owners can opt out of data sharing, they might lose key safety features. 

Many drivers don't realize that data collection features are also used for remote start, stolen vehicle tracking, automatic crash notifications, or over-the-air (OTA) software updates. Not having the latest updates for key features, like ADAS systems, increases the risk of systems not working properly. 

All About Cookies shared manufacturer specific information regarding what gets disabled if a user opts of data sharing/collection: 

• Tesla's policy states that fully deactivating vehicle connectivity/data collection (via factory contact) means losing OTA updates, remote services, and most in-car connected features. 

• Mazda's main data-sharing toggle disables Remote Controls, Find My Car, Vehicle Info, and Wi-Fi tethering. 

• Kia Connect helps deliver Remote Start, Driving Score, Find My Car, Roadside Assistance, and Automatic Crash Notification. Opting out of Kia Connect/location sharing would functionally disable them. Automatic Crash Notification specifically depends on sharing precise location with emergency. 

• General Motors Connected Service features delivered via OnStar's data collection include Remote Start, Vehicle Locate, Roadside Assistance, Navigation, Health/Maintenance Reports, Wallet Services. The Policy does not state whether/how opting out affects each feature individually. 

• Nissan: Three opt-out methods are listed for NissanConnect data collection; disabling it would end connected-vehicle features generally. 

• Volkswagen: ADAS and EDR (crash-triggered event) data is recorded onboard. There is no stated link between data-sharing opt-out and whether ADAS or crash-recording functionality is affected; full detail deferred to the owner manual. 

• Subaru Stolen Vehicle Recovery, DMS (DriverFocus), EyeSight, EDR are named as separate onboard systems; independent repair shops can access EDR/DMS data with their own tools, outside Subaru's control or any consumer opt-out mechanism. These features are not explicitly tied to the general data-sharing opt-out in the policy. 

The report details notable policy elements for how each company uses driver data. For example, Honda's policy allows it to infer "psychological trends, predispositions, behavior, attitudes, intelligence, abilities, aptitudes," while also collecting student ID information and the number and ages of your children.  

Mazdauses collected data to infer household income. 

To read the full report and analysis, click here.